51787139 has 2 divisors, whose sum is σ = 51787140. Its totient is φ = 51787138.

The previous prime is 51787129. The next prime is 51787147. The reversal of 51787139 is 93178715.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51787139 - 2⁴ = 51787123 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 51787096 and 51787105.

It is not a weakly prime, because it can be changed into another prime (51787129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25893569 + 25893570.

It is an arithmetic number, because the mean of its divisors is an integer number (25893570).

Almost surely, 2^51787139 is an apocalyptic number.

51787139 is a deficient number, since it is larger than the sum of its proper divisors (1).

51787139 is an equidigital number, since it uses as much as digits as its factorization.

51787139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 52920, while the sum is 41.

The square root of 51787139 is about 7196.3281609443. The cubic root of 51787139 is about 372.7411204074.

The spelling of 51787139 in words is "fifty-one million, seven hundred eighty-seven thousand, one hundred thirty-nine".